CR
Giant Ibis Thaumatibis gigantea



Taxonomy

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
A2cd+3cd+4cd; C2a(i) A2cd+3cd+4cd; C2a(i); D A2cd+3cd+4cd; C2a(i); D1

Red List history
Year Category Criteria
2016 Critically Endangered A2cd+3cd+4cd; C2a(i)
2015 Critically Endangered A2cd+3cd+4cd; C2a(i)
2013 Critically Endangered A2cd+3cd+4cd;C2a(i)
2012 Critically Endangered A2cd+3cd+4cd;C2a(i)
2010 Critically Endangered A2c,d; A3c,d; A4c,d; C2a(i)
2009 Critically Endangered A2c,d; A3c,d; A4c,d; C2a(i)
2008 Critically Endangered
2004 Critically Endangered
2000 Critically Endangered
1996 Critically Endangered
1994 Critically Endangered
1988 Threatened
Species attributes

Migratory status not a migrant Forest dependency High
Land mass type Land-mass type - continent
Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 120,000 medium
Number of locations -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 194 medium estimated 2014
Population trend Decreasing poor suspected -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) 80-100 - - -
Decline (10 years/3 generation past and future) 80-100 - - -
Number of subpopulations 3-10 - - -
Largest subpopulations 1-89 - - -
Generation length (yrs) 8 - - -

Population justification: An assessment of the global population was made in 2014 based on newly collected data and expert opinion (including estimates of 48 and 35 mature individuals at the highest density sites) (Loveridge and Ty 2015). The population was estimated at a minimum of 194 mature individuals which is equivalent to approximately 290 individuals.

Trend justification: An extremely rapid population decline is suspected to have occurred over the last three generations and is projected to occur over the next three generations, based on information from T. Clements (in litt. 2007), who has commented: Deforestation scenarios project that Cambodia will lose 50% or more of its forest habitat in the next 25 years, a greater portion of which is expected to be in the lowland areas inhabited by Giant Ibis. For example, recent assessments have shown that Cambodia lost 1-2% of its forest annually during 2002-2006. Giant Ibises are known to be highly sensitive to human disturbance, hence increasing deforestation and habitat fragmentation would have a disproportionate effect on the remaining ibis populations.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Cambodia N Extant Yes
Laos N Extant Yes
Thailand N Extinct Yes
Vietnam N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Cambodia Chhep
Cambodia Lomphat
Cambodia Mondulkiri - Kratie Lowlands
Cambodia Sekong River
Cambodia Upper Srepok Catchment
Cambodia Upper Stung Sen Catchment
Cambodia Western Siem Pang
Laos Dong Kalo
Laos Dong Khanthung
Laos Xe Kong Plains
Vietnam Yok Don

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Arable Land suitable non-breeding
Forest Subtropical/Tropical Moist Lowland major resident
Grassland Subtropical/Tropical Seasonally Wet/Flooded major resident
Wetlands (inland) Permanent Freshwater Lakes (over 8ha) major resident
Wetlands (inland) Permanent Freshwater Marshes/Pools (under 8ha) major resident
Altitude   Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Agro-industry farming Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Annual & perennial non-timber crops - Small-holder farming Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Livestock farming & ranching - Small-holder grazing, ranching or farming Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Gathering terrestrial plants - Unintentional effects (species is not the target) Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation
Biological resource use Hunting & trapping terrestrial animals - Intentional use (species is the target) Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Species mortality
Biological resource use Logging & wood harvesting - Unintentional effects: (large scale) [harvest] Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem conversion
Human intrusions & disturbance Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Species disturbance
Invasive and other problematic species, genes & diseases Problematic native species/diseases - Unspecified species Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Reduced reproductive success
Natural system modifications Dams & water management/use - Dams (size unknown) Timing Scope Severity Impact
Future Minority (<50%) Rapid Declines Low Impact: 4
Stresses
Ecosystem degradation, Ecosystem conversion
Natural system modifications Fire & fire suppression - Increase in fire frequency/intensity Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Residential & commercial development Timing Scope Severity Impact
Ongoing Minority (<50%) Rapid Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Transportation & service corridors Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species disturbance, Ecosystem conversion

Utilisation
Purpose Primary form used Life stage used Source Scale Level Timing
Food - human - - Non-trivial Recent

Recommended citation
BirdLife International (2017) Species factsheet: Thaumatibis gigantea. Downloaded from http://www.birdlife.org on 18/12/2017. Recommended citation for factsheets for more than one species: BirdLife International (2017) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 18/12/2017.